The present invention relates to a printing apparatus and, more particularly, to a laser beam printer using the electrophotographic or xerographic processes.
A printing apparatus has been developed, and is known in the art, in which a laser beam is modulated in accordance with image information coming from an electronic computer or the like. The modulated beam is focused on a photoreceptor while scanning through optical elements such as a light deflecting device and a lens to selectively expose the photoreceptor. Then, latent images are formed on the surface of the photoreceptor. The latent image on the photoreceptor faces a developing device to deposit toner particles on the charged image area. Thereafter, the developed image is transferred to a paper sheet by electrostatic force at a transfer station. The printed sheet is passed through a fixing device.
As disclosed in, e.g., U.S. Pat. No. 4,460,909, paper sheets for printing are stored in a stacker, and are fed to the transfer station one by one. A paper sheet on which a developed image is transferred by the transfer station is delivered on a tray while the developed image faces up.
However, in the above-mentioned arrangement, when a continuous printing operation is performed in accordance with image information from the computer, the order of pages of the printed paper sheets is reversed. More specifically, the paper sheet of the first page is stacked at a lowermost position on the tray, and the paper sheet of the last page is stacked on the uppermost position on the tray. Furthermore, when the paper sheet jams in the transfer station, since the transfer station is located inside the printer, it is difficult to recover the jamming sheet.